[clang] [Clang] Handle structs with inner structs and no fields (PR #89126)

[Eli Friedman via cfe-commits]

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@@ -844,7 +847,18 @@ const FieldDecl *CodeGenFunction::FindFlexibleArrayMemberField(
       if (const FieldDecl *Field =
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efriedma-quic wrote:

FieldNo and Layout are referring to fields of "RD"; the "Field" found in the recursive visit is a member of Record (or some subobject of Record).  So the code is doing math on completely unrelated offsets.  Checking getFieldCount is just masking the issue.

https://github.com/llvm/llvm-project/pull/89126